The effects of transcleral cryotherapy and diathermy on normal ocular growth in rabbits

Purpose. In determine the effects of transcleral cvclo-cryotherapy and cyclodiatherni) of anterior part of eyeball on the normal ocular growth. Methods. Twenty-four New Zealand While rahhits were used. Transcleral cryotherapy (n=12) and diathermy (n=12) was performed on the right eye of 3-4 weeks old rabbits, the left eje left unlreated lor cnntrol. The cryotherapy using a standard retinal cryoprobe with visuali/atinn h\ indirect ophthalmoseopy, and the diatlitrm> using a flat diathermy probe: \\ere applied idO1' to the retina anterior to the equator, except in areas where the long ciliary arteries and nerxes \\ere loeated. Biometrie ocular dimensions (anterior chamber depth, lens thickness, axial length) and intraocular pressure (K)P) \\ere measured e\-ery month until 3 months later. Results. All the ocular dimensions were increased with the increasing of aging. The mean axial length of diathermytreated e\es uas significantly smaller than the untreated control e\es from first to third month later (p- 0.01 ). In contrast, the mean si/e- of cr>otherapy-treated eye was similar \\ith the control e\es on the first and third month <p=0.1 7). hut it \\as smaller on the second month later. The anterior chamber depth, lens thickness and IOP were not significant!) different between the treated and untreated e>e. Besides. histological evidence showed the sciera of diathermy area \\as thinner, but the sciera ol'cr\olherap\ \\as not. Conclusions. The mechanisms of peripheral retinal ablation on the control of ocular growth ma} he through both ofietinal and local scierai effects.